/**
 * \file aes.h
 *
 *  Based on TropicSSL: Copyright (C) 2017 Shanghai Real-Thread Technology Co., Ltd
 *
 *  Based on XySSL: Copyright (C) 2006-2008  Christophe Devine
 *
 *  Copyright (C) 2009  Paul Bakker <polarssl_maintainer at polarssl dot org>
 *
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *    * Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *    * Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *    * Neither the names of PolarSSL or XySSL nor the names of its contributors
 *      may be used to endorse or promote products derived from this software
 *      without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 *  TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 *  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#ifndef TINY_CRYPT_AES_H__
#define TINY_CRYPT_AES_H__

#define AES_ENCRYPT     1
#define AES_DECRYPT     0

/**
 * \brief          AES context structure
 */
typedef struct
{
    int nr;                 /*!<  number of rounds  */
    unsigned long *rk;      /*!<  AES round keys    */
    unsigned long buf[68];  /*!<  unaligned data    */
} tiny_aes_context;

#ifdef __cplusplus
extern "C" {
#endif

/**
 * \brief               AES key schedule (encryption)
 *
 * \param ctx           AES context to be initialized
 * \param key           encryption key
 * \param keysize       must be 128, 192 or 256
 */
void tiny_aes_setkey_enc(tiny_aes_context *ctx, unsigned char *key, int keysize);

/**
 * \brief               AES key schedule (decryption)
 *
 * \param ctx           AES context to be initialized
 * \param key           decryption key
 * \param keysize       must be 128, 192 or 256
 */
void tiny_aes_setkey_dec(tiny_aes_context *ctx, unsigned char *key, int keysize);

/**
 * \brief               AES-ECB block encryption/decryption
 *
 * \param ctx           AES context
 * \param mode          AES_ENCRYPT or AES_DECRYPT
 * \param input         16-byte input block
 * \param output        16-byte output block
 */
void tiny_aes_crypt_ecb(tiny_aes_context *ctx,
                        int mode,
                        unsigned char input[16], unsigned char output[16]);

/**
 * \brief               AES-CBC buffer encryption/decryption
 *
 * \param ctx           AES context
 * \param mode          AES_ENCRYPT or AES_DECRYPT
 * \param length        length of the input data
 * \param iv            initialization vector (updated after use)
 * \param input         buffer holding the input data
 * \param output        buffer holding the output data
 */
void tiny_aes_crypt_cbc(tiny_aes_context *ctx,
                        int mode,
                        int length,
                        unsigned char iv[16],
                        unsigned char *input, unsigned char *output);

/**
 * \brief               AES-CFB128 buffer encryption/decryption
 *
 * \param ctx           AES context
 * \param mode          AES_ENCRYPT or AES_DECRYPT
 * \param length        length of the input data
 * \param iv_off        offset in IV (updated after use)
 * \param iv            initialization vector (updated after use)
 * \param input         buffer holding the input data
 * \param output        buffer holding the output data
 */
void tiny_aes_crypt_cfb128(tiny_aes_context *ctx,
                           int mode,
                           int length,
                           int *iv_off,
                           unsigned char iv[16],
                           unsigned char *input, unsigned char *output);

/**
 * \brief               AES-CFB8 buffer encryption/decryption
 *
 * \param ctx           AES context
 * \param mode          AES_ENCRYPT or AES_DECRYPT
 * \param length        length of the input data
 * \param iv            initialization vector (updated after use)
 * \param input         buffer holding the input data
 * \param output        buffer holding the output data
 */
void tiny_aes_crypt_cfb8(tiny_aes_context *ctx,
                         int mode,
                         int length,
                         unsigned char iv[16],
                         unsigned char *input,
                         unsigned char *output);

/**
 * \brief               AES-CTR buffer encryption/decryption
 *
 * \param ctx           AES context
 * \param length        length of the input data
 * \param nc_off        offset in the current stream_block
 * \param nounce        The 128-bit nonce and counter
 * \param stream_blk    The saved stream-block for resuming
 * \param input         buffer holding the input data
 * \param output        buffer holding the output data
 */
void tiny_aes_crypt_ctr(tiny_aes_context *ctx,
                       int length,
                       int *nc_off,
                       unsigned char nounce[16],
                       unsigned char stream_blk[16],
                       unsigned char *input,
                       unsigned char *output);

/**
 * \brief               AES-OFB buffer encryption/decryption
 *
 * \param ctx           AES context
 * \param length        The length of the input data.
 * \param iv_off        The offset in IV (updated after use).
 * \param iv            The initialization vector (updated after use).
 * \param input         The buffer holding the input data.
 * \param output        The buffer holding the output data.
 */
void tiny_aes_crypt_ofb(tiny_aes_context *ctx,
                        int length,
                        int *iv_off,
                        unsigned char iv[16],
                        unsigned char *input,
                        unsigned char *output);

#ifdef __cplusplus
}
#endif
#endif              /* aes.h */
